The invention relates to the field of game rackets used for sports employing a ball or the like, for example tennis, squash or badminton rackets.
It relates more particularly to rackets in which the string pattern carried by the frame comprises a grid parallel to the longitudinal axis of the handle and composed of vertical strings and a grid perpendicular to the former and composed of cross strings, these vertical strings and cross strings being interlaced, passing alternately above and then below the elements of the other grid.
The string pattern is obtained from at least one string of defined length which, outside the string pattern, passes through the frame of the racket to form a loop having a varied shape, depending on the rackets, and coming to bear on the frame.
The production of the string pattern within a completely manual operation or a manual operation with the assistance of a string bench is carried out according to known techniques.
In addition to the specific stringing operations, the connection between the stringing and the frame also plays an important part in the stability and reliability of the string pattern. Shank-carrying cleats are therefore known, which are mounted on the frame for the engagement of the shanks into holes made for this purpose in the frame. The stringing therefore passes through the frame by way of the shanks intended for guiding and protecting the string passing through them.
Shank-carrying cleats are known in the prior art which are produced from flexible material of the rubber type or from rigid material, so as to serve as a support for the loops of the stringing passing through the frame.
Existing rackets have a major disadvantage in that it is difficult to influence the dynamic behavior of their string pattern by means which are simple to use.
The object of the present invention is to obtain flexibility or elasticity in the string/frame connection, with controlled and, where appropriate, changing rigidity during the tensioning of the stringing or in the event of the impact of a ball.
An additional object is aimed at obtaining a damping of the shocks and vibrations undergone by the string pattern and felt by the player.
The objects of the present invention are achieved with the aid of a racket comprising a frame, in which through-holes are made, shank-carrying cleats, the shanks of which are engaged in the holes, and a stringing mounted on the frame by means of the shank-carrying cleats, so as to produce a string pattern within the frame, said shank-carrying cleats each having at least one bearing surface which is located between each pair of adjacent shanks and on which a stringing loop bears. According to the invention, at least some of these bearing surfaces are assigned to gaps located between said bearing surfaces and the frame.
The objects of the present invention are also achieved with the aid of a shank-carrying cleat which comprises at least two shanks and is intended to be mounted on the frame of a racket and which has at least one bearing surface between two adjacent shanks so as to provide support for stringing. According to the invention, at least one bearing surface is assigned to a gap located between said bearing surface and the frame or between said bearing surface and a part of the cleat intended for coming to bear on or coming opposite the frame.
Thus, in one embodiment of the invention, the frame of the racket is, for example tubular, and each of the holes passing through its respectively inner and outer walls for the passage of a vertical string or of a cross string forms a receptacle for a shank for guiding this vertical string or cross string, and this shank is integral, together with a plurality of other shanks, with a shank-carrying cleat made of semirigid synthetic material molded to the shape of that part of the frame to which it is to be affixed, and at the same time giving the shanks the orientation which they must have when they are engaged in the through-holes of this frame, said cleat comprising, between each group of two contiguous shanks, a bearing surface for the support of the string.
In the embodiments of the racket according to the invention, the gaps extend over the outer periphery of the frame, either in a longitudinal direction or in a transverse direction, and issue or not on the lateral and/or longitudinal flanks of the bearing surfaces.
In another embodiment of the shank-carrying cleats according to the invention, the bearing surfaces have a hole issuing, on the one hand, on the bearing zone of the string and, on the other hand, on the gap.
In other embodiments of the invention, at least some of the gaps are filled with a flexible material in order to damp the deformations undergone by the corresponding bearing surfaces in the event of tension or a shock on the stringing.
In one embodiment, advantageously the flexible material comes into contact with the string and the frame of the racket.